JPH0867800A - Curing agent composition for epoxy resin - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hardener composition for an aqueous epoxy resin composition having excellent chemical resistance.

SOLUTION: There is provided a composition consisting essentially of the following components: (A1) polyamines of formulas I and/or II [wherein R₁ and R₂ are each H or methyl; x=1-3; y=0-2 (x+y≤4); and z=0-2]; or (A2) a mixture of amines of formulas I and/or II with another polyamine; (B) an aliphatic, alicyclic, or araliphatic alcohol or a corresponding alcohol mixture; and (C) an alkyl- and/or aralkyl-substituted monophenols or a corresponding monophenol mixture [in an amount of 10-50% of the total weight of the above components].

COPYRIGHT: (C)1996,JPO

Description

Detailed Description of the Invention

[0001]

The present invention relates to compositions based on methylene-linked cycloalkylarylpolyamines, aliphatic, cycloaliphatic or araliphatic alcohols and alkylated or aralkylated phenols, as hardeners. It relates to the use of these compositions, the epoxy compositions cured by them and the materials cured thereby.

[0002]

BACKGROUND OF THE INVENTION Purely aromatic polyamines, which have been frequently used in the past, in particular 4,4'-diaminodiphenylmethane, can be used only under exceptional conditions because of the toxicological hazards, and therefore methylene. Mixtures of polyamines with a carbon structure in the form of attached cycloalkyl groups and aromatic groups are used more and more recently for curing epoxy resins. Mixtures of methylene-bonded cycloarylpolyamines and their use as epoxy resin hardeners are described in particular in EP 0554
No. 823, and provides an epoxy resin coating with generally good resistance to chemicals except aqueous carboxylic acids such as acetic acid. Aliphatic, cycloaliphatic or especially alaliphatic alcohols are usually added to polyamines as viscosity reducing agents. According to EP 0554823, it is also possible to add further substituted phenols as accelerators to the two components of these hardeners. The patent application mentioned above is especially concerned with 41.5% by weight of a mixture of methylene linked cycloalkylaryl polyamines, 41.5% by weight of benzyl alcohol and 3.5 of bisphenol A.
Disclosed is a curing agent for an epoxy resin containing wt%.

[0003]

The object of the present invention is to provide methylene-bonded cycloalkylarylpolyamines and aliphatic, cycloaliphatic or aralkyl compounds which have better resistance to aqueous carboxylic acids than the corresponding conventional hardener mixtures. A liquid epoxy resin based on rifatic alcohol is provided.

[0004]

The present invention therefore essentially comprises the following components A1) formula (I) and / or (II) (Wherein R ₁ and R ₂ each independently represent a hydrogen atom or a methyl group; x represents an integer of 1 to 3; and y represents an integer of 0 to 2; and the sum of x and y is 4 or less; and z represents an integer of 0 to 2); or A2) a mixture of a polyamine represented by the formula (I) and / or (II) with another polyamine; B ) Aliphatic, cycloaliphatic or alaliphatic (araliph
atic) alcohols or mixtures of corresponding alcohols;
And C) Alkyl- and / or aralkyl-substituted monophenols or mixtures of the corresponding monophenols [component C) are 10 to 50% of the total weight of the above components. ]
To a composition consisting of

Preferred polyamines have the formulas R ₁ and R
A polyamine of formula (I) and / or (II), wherein ₂ is a hydrogen atom. Representative examples of polyamines of formula (I) and / or (II) include bis (4-aminocyclohexyl) methane, 2,4-bis (4-aminocyclohexylmethyl) cyclohexylamine, trimethylenetetracyclohexylamine; 4- (4'-aminobenzyl) cyclohexylamine, 2,4-bis (4-aminocyclohexylmethyl) aniline and partially hydrogenated trimethylenetetraaniline. The production of such polyamines is known to the person skilled in the art and according to the method of EP 0554823 the corresponding dinuclear condensate 85 to 50% by weight and the corresponding tri- and polynuclear condensate 15 to 50% by weight. The aniline and / or o-toluidine and the condensate of formaldehyde and hydrogen atom of 3.5 to 27.7 MPa.
Pressure (500 to 4000 psig), and 1
In the presence of a hydrogenation catalyst in the temperature range of 50 to 250 ° C.,
It is obtained by reacting for 1 to 4 hours, and separating undesired components partially or completely.

A preferred embodiment of the composition according to the invention consists essentially of components A2), B) and C), wherein A2) is the polyamine mixture obtained by this process. Such polyamine mixtures also contain minor amounts of monoamines, typically 4-aminocyclohexyl-4-hydroxycyclohexylmethane and minor amounts of unhydrogenated condensates of aniline and / or o-toluidine and formaldehyde and these Some of the mixtures are commercially available.

EP 0554823 discloses various examples of corresponding polyamine mixtures. Particularly preferred is 2,4-bis (4-aminocyclohexylmethyl) cyclohexylamine 20 to 40% by weight;
-Bis (4-aminocyclohexylmethyl) aniline 4
0 to 70% by weight; 0 to 10% by weight of bis (4-aminocyclohexyl) methane and optionally a mixture of further tetranuclear or polynuclear polyamines. In these mixtures, preferably about 10 to 20%, in particular about 14%, of all amino groups are aromatic.

In addition to the polyamine components A1) or A2, the novel composition comprises another amine, in particular an aliphatic, cycloaliphatic and / or alaliphatic polyamine, typically 50% by weight, based on the total amine. It can be included in an amount up to. The total amount of polyamines A1) or A2) in the novel composition is preferably in the range 30-70% by weight.

Component B) is preferably added to the novel composition in an amount of 20 to 50% by weight, based on the total amount of polyamine and components B) and C). Component B) acts especially as a viscosity reducing agent. It is preferably a straight-chain or branched-chain aliphatic alcohol which contains 1 to 10 carbon atoms and is liquid at ambient temperature, or 5 to 1
It is a liquid cycloaliphatic or alaliphatic alcohol containing 0 carbon atoms. In this regard, the term "aliphatic, cycloaliphatic and alaliphatic" further refers to the corresponding alcohols containing one or more heteroatoms, preferably one or more oxygen, sulfur or nitrogen atoms. Also includes.

Component B) is more preferably an araliphatic alcohol, more particularly furfuryl alcohol or benzyl alcohol or mixtures thereof.

Component C) of the novel composition is especially 3 to 1.
It consists of an alkyl group with 8 carbon atoms and of a monophenol with 1, 2 or 3 substituents selected from phenylalkyl groups. Illustrative examples of suitable alkyl groups include, among others, n-propyl, isopropyl, n-butyl, sec-butyl, sec-butyl, n-amyl, sec-amyl, sec-amyl, branched or It is an unbranched hexyl group, heptyl group, octyl group, nonyl group, dodecyl group or octadecyl group. Phenylaryl groups are preferably phenyl- (C1 -C6) alkyl groups. Particularly preferred examples of such phenylaryl groups are of the formula Is a group represented by. In the art, phenols with this substituent are often abbreviated as "cumylphenol".
Called. This also applies here, unless stated otherwise. The individual substituents are preferably those in the ortho- or para-position to the phenolic hydroxyl group, a pair of substituents in the 2,4- or 2,6-position and the 2,4,6-position. And three substituents in. 2 representatives of suitable commercially available monophenols
-Isopropylphenol, 2-secondary-butylphenol, 4-secondary butylphenol, 2-tertiary butylphenol, 4-tertiary butylphenol, 4-tertiary butylphenol, 2-tertiary amylphenol, 4-tertiary amylphenol, 4 -N-octylphenol, 4- (1,
1,3,3-Tetramethylbutyl) phenol (= 4-
Tertiary octylphenol), 4-nonylphenol, 4
-Dodecylphenol, 4-octadecylphenol,
4-cumylphenol, 2,4-dicumylphenol,
2-tert-butyl-para-cresol, 6-tert-butyl-
Ortho-cresol, 4-tertiary butyl-ortho-cresol, 6-tertiary butyl metacresol, 4,6-ditertiary butylphenol, 2-second-4-tertiary butylphenol, 2,4-di-tertiary Amylphenol, 6-tert-butyl-2,4-xylenol, 4,6-di-tert-butyl-
Ortho-cresol, 4-tert-butyl-2,6-di-tert-butylphenol or 2,6-di-tert-butyl-4-
It is nonylphenol. A very particularly preferred monophenol is of the formula in which it is in the para position to the alkyl substituent of 9 to 12 carbon atoms or preferably to the hydroxy group of the phenol. A monophenol having a group represented by, more particularly a p-nonylphenol group and p-dodecylphenol or a mixture of the two.

A preferred example of the novel composition is Component A
40 to 6 based on the total amount of 1), B) and C)
0% by weight of component A1) or A2), 20 to 4
Component B) in an amount of 0% by weight and component C) in an amount of 10 to 40% by weight, the total percentage of all of which is 10
0.

The novel composition is particularly suitable as a hardener for epoxy resins. Accordingly, the invention also relates to a curable composition comprising a) at least one epoxy resin and b) the composition described above as a curing agent.

Suitable for use in the novel cured composition, the epoxy resin (a) has more than one 1,2 in the molecule.
-Standard epoxy resin in epoxy resin technology, containing epoxy groups. Typical epoxy resins are:

I) Polyglycidyl and poly (β-methylglycidyl) obtained by reacting a compound containing at least two carboxyl groups in the molecule with epichlorohydrin or β-methylepichlorohydrin
ester. The reaction is conveniently carried out in the presence of base.

The compounds containing at least two carboxyl groups in the molecule may, if appropriate, be aliphatic polycarboxylic acids. Examples of such polycarboxylic acids are oxalic acid, succinic acid, glutaric acid, adipic acid, pimelic acid,
It is sebacic acid, suberic acid, azelaic acid or dimerized or trimerized linolenic acid. However, cycloaliphatic polycarboxylic acids such as tetrahydrophthalic acid, 4-methyltetrahydrophthalic acid, hexahydrophthalic acid, 4-methylhexahydrophthalic acid or cyclohexane-1,4-dicarboxylic acid can also be used. Aromatic polycarboxylic acids can also be used, typically phthalic acid,
Isophthalic acid and terephthalic acid.

II) Reaction of a compound containing at least two free alcoholic hydroxyl groups and / or phenolic hydroxy groups with epichlorohydrin or β-methylepichlorohydrin under alkaline conditions or in the presence of an acid catalyst. And poly (β-methylglycidyl) ether obtained by subsequent treatment with alkali.

Glycidyl ethers of this type are typically derived from acyclic alcohols such as ethylene glycol, diethylene glycol and higher poly (oxyethylene) glycols, 1,2-propanediol or poly (oxypropylene) glycols, 1, 3-propanediol, 1,4-butanediol, poly (oxytetramethylene) glycol, 1,5-pentanediol,
It is derived from 1,6-hexanediol, 2,4,6-hexanetriol, glycerol, 1,1,1-trimethylolpropane, pentaerythritol, sorbitol and from polyepichlorohydrin. They may also be derived from cycloaliphatic alcohols such as 1,4-cyclohexanedimethanol, bis (4-hydroxycyclohexyl) methane or 2,2-bis (4-hydroxycyclohexyl) propane, or They may contain aromatic nuclei such as N, N'-bis (2-hydroxyethyl) aniline or p, p'-bis (2-hydroxyethylamino) diphenylmethane.

Glycidyl ethers may also be derived from mononuclear phenols, typically resorcinol or hydroquinone, or they are bis (4
-Hydroxyphenyl) methane, 4,4'-dihydroxybiphenyl, bis (4-hydroxyphenyl) sulfone, 1,1,2,2-tetrakis (4-hydroxyphenyl) ethane, 2,2-bis (4-hydroxyphenyl) ) Propane, 2,2-bis (3,5-dibromo-4-)
Hydroxyphenyl) propane; and aldehydes such as formaldehyde, acetaldehyde, chloral or furfuraldehyde and phenols or one carbon atom in the nucleus thereof
From a novolak obtained by condensation with a phenol substituted with an alkyl group of from 9 to 9, such as 4-chlorophenol, 2-methylphenol or 4-tert-butylphenol, or by the condensation of a bisphenol of the type cited above, Can be induced.

III) Epichlorohydrin and at least 2
Poly- (N-glycidyl) compounds obtained by dehydrochlorination of reaction products with amines containing one amino hydrogen atom. These amines are typically aniline, n-butylamine, bis (4-aminophenyl) methane, m-xylylenediamine or bis (4-methylaminophenyl) methane. Poly (N-glycidyl) compounds also include triglycidyl isocyanurate, N, N'-diglycidyl derivatives of cycloalkylene ureas such as ethylene urea or 1,3-propylene urea and hydantoin compounds such as 5,5-dimethylhydantoin. Also includes diglycidyl derivatives.

IV) Poly (S-glycidyl) compounds, preferably bis (S-glycidyl) derivatives derived from dithiols such as 1,2-ethanediol or bis (4-mercaptomethylphenyl) ether.

V) Bis (2,3-epoxycyclopentyl) ether, 2,3-epoxycyclopentylglycidyl ether, 1,2-bis (2,3-epoxycyclopentyloxy) ethane or 3,4-epoxycyclohexylmethyl-3 Alicyclic epoxy resin containing ', 4'-epoxycyclohexanecarboxylate.

It is also possible to use epoxy resins in which the 1,2-epoxy group is a 1,2-epoxy group in which different heteroatoms or functional groups are bonded. These compounds are typically N, N, O-triglycidyl derivatives of 4-aminophenol, glycidyl ether-glycidyl esters of salicylic acid, N-glycidyl-N '-(2-
Glydyloxypropyl) -5,5-dimethylhydantoin or 2-glycidyloxy-1,3-bis (5,5)
5-dimethyl-1-glycidylhydantoin-3-yl) propane.

It is preferred to use liquid or viscous polyglycidyl ethers or esters as epoxy resin (a) in the novel curable compositions, preferably liquid or viscous diglycidyl ethers of bisphenol.

The epoxy compounds described above are known and some are commercially available. Mixtures of epoxy resins can also be used.

The amount of curative will depend on the chemistry of the curative and the desired properties of the curable mixture and the cured product. The maximum amount can be easily determined. The amount used is usually 0.75 to 1.25 equivalents of active hydrogen bonds bonded to the amino nitrogen atom per epoxide equivalent.

The novel compositions can be prepared in a known manner by mixing the components by hand stirring or known mixing equipment, typically a stirrer, kneader or roll mill. The composition has only a relatively low viscosity.

Depending on their utility, conventional modifiers, typically including fillers, pigments, dyes, flow control agents or plasticizers, may be added to the compositions of this invention.

The novel composition can be cured in one or more stages in a manner known per se. Curing is usually at room temperature or below room temperature, or by heating the composition to temperatures up to 120 ° C., preferably 5 to 50.
It is carried out in the temperature range of ° C. Curing is also unaffected by the relatively high relative humidity.

As mentioned at the beginning, the moldings or coatings obtained from the compositions according to the invention are suitable for excellent chemicals, in particular for carboxylic acids, for example in aqueous acetic acid at concentrations up to 30% by weight and for highly concentrated alcohols. Be resistant.
They form another object of the invention.

[0031]

The present invention will be described in more detail by the following examples. Example 1 : Registered trademark Ancamine X2168
[Commercial mixture of polyamines of formulas (I) and (II)]
1.75 g is heated to 60 ° C. and benzyl alcohol is added.
Add 75 g. The mixture is then cooled with stirring,
2,6-bis-tert-butyl-4-nonylphenol 1.
Add 0 g. The mixture has a viscosity of 5100 mPa · s at 25 ° C.

Example 2-6 : A similar curing agent composition is prepared with the phenols listed in the table below. The viscosity in the table is measured at 25 ° C. Example Phenol amount Viscosity 2 4-Nonylphenol 1.0 g 9920 mPa · s 3 4-cumylphenol 0.5 g 7840 mPa · s 4 2,4-dicumylphenol 0.5 g 10610 mPa · s 5 2,4-bis-tertiary amyl Phenol 0.5 g 7200 mPa · s 6 2-tert-butyl-4-cumylphenol 0.5 g 9440 mPa · s

Example 7: 3.5 g of the curing agent of Example 1
Epoxy number of 5.25-5.40 eq / kg and 10
Mix thoroughly with 5.38 g of diglycidyl ether of bisphenol A having a viscosity of 000-12000 mPas. After mixing and short-term temperature adjustment, the mixture is at 64
It has 00 mPa · s. After a further 5 minutes at 25 ° C., the viscosity increases to 7040 mPa · s. Mix 0.200
It is applied to a glass plate with a mm application knife and it is 20
Fully cured at ℃.

Example 8: 3.5 g of the curing agent of Example 1
Epoxy number of 5.25-5.40 eq / kg and 10
Mix thoroughly with 5.41 g of diglycidyl ether of bisphenol A having a viscosity of 000-12000 mPas. The mixture is brushed onto a sandblasted steel plate. After several hours at 20 ° C. a transparent hard layer forms. The mixture was applied to a glass plate with a 0.200 mm application knife and cured for 1 day at 20 ° C.
soz) pendulum hardness according to the method [BYK-
Pendulum hardness tester supplied by SEMI (BYK-Chemie)
(measured by (pendulum hardness tester)] is 11
It is 5s. After curing for 7 days at 20 ° C, the Pelso hardness is 28.
It increases to 4s and 14 days later to 293s. Pendulum hardness after 7 days is 97 s when curing is carried out at 5 ° C.
And 14 days later is 146s. The mixture is also 2
0 ° C and 100% relative humidity and 5 ° C and 45
% Relative humidity cures well without surface haze or simply with very little surface haze.

Example 9 : Trademark Ancamine
X2168 [commercial mixture of polyamines of formulas (I) and (II)] 1.75 g, benzyl alcohol 0.75 g
And 4-nonylphenol 1.4 g 5.25-
Epoxy number of 5.40 eq / kg and 10,000-1
Mix thoroughly with 5.41 g of diglycidyl ether of bisphenol A having a viscosity of 2000 mPas. The mixture is brushed onto a sandblasted steel plate. 20 ° C
In a few hours, a transparent hard layer is formed. When the mixture was applied to a glass plate with a 0.200 mm application knife and cured for 1 day at 20 ° C., the pendulum hardness according to the Persoz method [BYK-Semi (BYK
Pendulum hardness tester (pendulum supplied by K-Chemie)
hardness tester)] is 97 s.
After curing at 20 ° C. for 7 days, the Pelso hardness increases to 246 s. If the curing is carried out at 5 ° C., the pendulum hardness after 7 days is 91 s and after 14 days is 133 s. This mixture also cures well at 20 ° C. and 100% relative humidity and at 5 ° C. and 45% relative humidity without surface haze or simply with very little surface haze.

The resistance to chemicals is determined after 8 days of curing at 20 ° C., as follows: The steel sheet coated with the mixture of Examples 8 and 9 is half-wetted in the test medium in the clamping device. wetted), and inspect daily. The layers withstand chemicals for the number of days specified in the table below without blistering or peeling from the steel sheet. Test medium Mixture of example 8 9 50% CH ₃ COOH / H ₂ O 6 4 30% CH ₃ COOH / H ₂ O 14 14 10% CH ₃ COOH / H ₂ O>21> 21 96% C ₂ H ₅ OH 12 4 xylene> 21 12

Claims (14)

[Claims] 1. Essentially the following components: A1) Formulas (I) and / or (II) (Wherein R ₁ and R ₂ each independently represent a hydrogen atom or a methyl group; x represents an integer of 1 to 3; and y represents an integer of 0 to 2; and the sum of x and y is 4 or less; and z represents an integer of 0 to 2); or A2) a mixture of a polyamine represented by the formula (I) and / or (II) with another polyamine; B ) Aliphatic, cycloaliphatic or alaliphatic (araliph
atic) alcohols or mixtures of corresponding alcohols;
And C) Alkyl- and / or aralkyl-substituted monophenols or mixtures of the corresponding monophenols [component C) are 10 to 50% of the total weight of the above components. ]
A composition consisting of. 2. Component A1) or A2) corresponds to 2
85 to 50% by weight of nuclear condensate and corresponding tri-
And a condensate of aniline and / or o-toluidine and formaldehyde consisting of 15 to 50% by weight of a polynuclear condensate and a hydrogen atom in an amount of 3.5 to 27.7M.
By reacting at a pressure of Pa (500 to 4000 psig) and a temperature range of 150 to 250 ° C. in the presence of a hydrogenation catalyst for 1 to 4 hours, and partially or completely separating undesired components. The composition of claim 1 which is a mixture of the resulting polyamines. 3. As the polyamine, 2,4-bis (4-
Aminocyclohexylmethyl) cyclohexylamine 20
40% to 40% by weight; 2,4-bis (4-aminocyclohexylmethyl) aniline 40 to 70% by weight; A composition according to claim 1 comprising and preferably 10 to 20% of all amino groups are aromatic. 4. An aliphatic, cycloaliphatic, and / or alaliphatic polyamine is further added to the polyamine component A1).
Alternatively, the composition according to claim 1, which is mixed with A2). 5. Polyamine A1) or A2) is added to 30-
The composition according to claim 1, comprising in an amount of 70% by weight. 6. Polyamine and components B) and C)
A composition according to claim 1, comprising component B) in an amount of 20 to 50% by weight, based on the total amount of 7. Component A1) or A2) in an amount of 40 to 60% by weight, component B) and 1 in an amount of 20 to 40% by weight, based on the total amount of components A1), B) and C).
A composition according to claim 1, comprising component C) in an amount of 0 to 40% by weight, the total percentage of all of which is 100. 8. A composition according to claim 1, wherein component B) consists of furfuryl alcohol or benzyl alcohol or mixtures thereof. 9. Component C) is one or more monophenols each having 1, 2 or 3 substituents selected from alkyl groups having 3 to 18 carbon atoms or from phenylalkyl groups. The composition of claim 1 which comprises: 10. A formula, wherein the monophenol is in the alkyl position of 9 to 12 carbon atoms or, preferably, para to the hydroxyl group of the phenol. The composition according to claim 9, which has a substituent represented by: 11. The composition according to claim 10, wherein the monophenol is p-nonylphenol or p-dodecylphenol or a mixture thereof. 12. A curing agent for an epoxy resin comprising the composition according to claim 1. 13. A curable composition comprising a) at least one epoxy resin and b) the composition according to claim 1 as a curing agent. 14. A molded article or coating obtained by curing the composition according to claim 13.